Update README.md

- Add audio channels setting (auto/mono/stereo) to MPV properties
- Implement UI controls in settings panel and player right controls
- Enable immediate MPV property application when setting changes
- Update default playback type to LOCAL and sample rate to 48kHz

src/renderer/features/player/components/right-controls.tsx

@@ -224,16 +224,22 @@ export const RightControls = () => {
                         icon={
                             playbackSettings.mpvProperties.audioChannels === 'mono'
                                 ? 'volumeNormal'
-                                : 'volumeMax'
+                                : playbackSettings.mpvProperties.audioChannels === 'stereo'
+                                  ? 'volumeMax'
+                                  : 'volumeMute'
                         }
                         iconProps={{
                             size: 'lg',
                         }}
                         onClick={(e) => {
                             e.stopPropagation();
-                            const current =
-                                playbackSettings.mpvProperties.audioChannels || 'stereo';
-                            const next = current === 'mono' ? 'stereo' : 'mono';
+                            const current = playbackSettings.mpvProperties.audioChannels || 'auto';
+                            const next =
+                                current === 'auto'
+                                    ? 'mono'
+                                    : current === 'mono'
+                                      ? 'stereo'
+                                      : 'auto';
                             setSettings({
                                 playback: {
                                     ...playbackSettings,
@@ -245,15 +251,15 @@ export const RightControls = () => {
                             });
                             // Apply to MPV immediately
                             mpvPlayer?.setProperties({
-                                'audio-channels': next,
+                                'audio-channels': next === 'auto' ? undefined : next,
                             });
                         }}
                         size="sm"
                         tooltip={{
                             label:
                                 playbackType === PlaybackType.WEB
-                                    ? `Audio: ${playbackSettings.mpvProperties.audioChannels || 'stereo'} (MPV only)`
-                                    : `Audio: ${playbackSettings.mpvProperties.audioChannels || 'stereo'}`,
+                                    ? `Audio: ${playbackSettings.mpvProperties.audioChannels || 'auto'} (MPV only)`
+                                    : `Audio: ${playbackSettings.mpvProperties.audioChannels || 'auto'}`,
                             openDelay: 0,
                         }}
                         variant="subtle"

src/renderer/features/settings/components/playback/mpv-settings.tsx

@@ -33,7 +33,7 @@ export const getMpvSetting = (
 ) => {
     switch (key) {
         case 'audioChannels':
-            return { 'audio-channels': value };
+            return { 'audio-channels': value === 'auto' ? undefined : value };
         case 'audioExclusiveMode':
             return { 'audio-exclusive': value || 'no' };
         case 'audioSampleRateHz':
@@ -55,7 +55,7 @@ export const getMpvSetting = (
 
 export const getMpvProperties = (settings: SettingsState['playback']['mpvProperties']) => {
     const properties: Record<string, any> = {
-        'audio-channels': settings.audioChannels || 'stereo',
+        'audio-channels': settings.audioChannels === 'auto' ? undefined : settings.audioChannels,
         'audio-exclusive': settings.audioExclusiveMode || 'no',
         'audio-samplerate':
             settings.audioSampleRateHz === 0 ? undefined : settings.audioSampleRateHz,
@@ -278,15 +278,15 @@ export const MpvSettings = () => {
             control: (
                 <Select
                     data={[
+                        { label: 'Auto', value: 'auto' },
                         { label: 'Mono', value: 'mono' },
                         { label: 'Stereo', value: 'stereo' },
                     ]}
-                    defaultValue={settings.mpvProperties.audioChannels || 'stereo'}
+                    defaultValue={settings.mpvProperties.audioChannels || 'auto'}
                     onChange={(e) => handleSetMpvProperty('audioChannels', e)}
                 />
             ),
-            description:
-                'Select the audio channel mode. Stereo is the default, mono downmixes to a single channel.',
+            description: 'Select the audio channel mode. Auto lets MPV decide based on the source.',
             isHidden: settings.type !== PlaybackType.LOCAL,
             title: 'Audio Channels',
         },

src/renderer/store/settings.store.ts

@@ -124,7 +124,7 @@ const TranscodingConfigSchema = z.object({
 });
 
 const MpvSettingsSchema = z.object({
-    audioChannels: z.enum(['mono', 'stereo']).optional(),
+    audioChannels: z.enum(['auto', 'mono', 'stereo']).optional(),
     audioExclusiveMode: z.enum(['no', 'yes']),
     audioFormat: z.enum(['float', 's16', 's32']).optional(),
     audioSampleRateHz: z.number().optional(),
@@ -658,7 +658,7 @@ const initialState: SettingsState = {
         mediaSession: false,
         mpvExtraParameters: [],
         mpvProperties: {
-            audioChannels: 'stereo',
+            audioChannels: 'auto',
             audioExclusiveMode: 'no',
             audioFormat: undefined,
             audioSampleRateHz: 48000,